Anyone using Collector at a Large Scale Enterprise Level?

[ScottFierro]

Would like to discuss implementation and usage of Collector for ArcGIS with anyone who has leveraged it to the tune of 500 - 1,000 named users. The topics of interest will be AD FS, administration of named users and groups in conjunction with AD, back-end infrastructure impacts to your ArcGIS Servers.

[ScottFierro]

It appears I might be asking for something nobody else or nearly nobody else is doing so my odds of touching base with someone on this is minimal.

So, then to dissect this is anyone utilizing Active Directory Federated Servers (ADFS) and if you are what have been some challenges managing the users and groups in AD against the roles and groups in ArcGIS Online?